DIRECT ACTIVATORY INFLUENCE OF PREOPTIC S OMNOGENIC AREA ON THALAMIC SYNCHRONIZING SYSTEM

In order to reveal the mechanisms of participation of the preoptic hyp othalamic area in sleep-wake cycle regulation the effects of its elect rical stimulation on activity of the thalamic median center were studi ed in chronic experiments in cats. Ipsi- and contralateral projections from the lateral preoptic area to the thalamic median center were ele ctrophysiologically demonstrated. Activatory influence of the preoptic area was shown on the thalamic mechanisms of spindle activity generat ion, The obtained data suggest the interaction of the preoptic area wi th the structures of non-specific thalamus via the direct pathways to be one of the mechanisms of the preoptic area participation in sleep i nitiation and formation of the slow-wave sleep.